An electronic device refers to a device that performs a specific function according to an equipped program, such as an electronic scheduler, a portable multimedia reproducer, a mobile communication terminal, a tablet personal computer (PC), an image/sound device, a desktop/laptop PC, or a vehicular navigation system (such as global position system (GPS)), as well as a home appliance. For example, such an electronic device may output information stored therein as sound or an image. In addition, the electronic device may provide a super-high speed based on a degree of integration of the electronic device. Furthermore, a large capacity wireless communication system has become popular to support various functions that have recently been equipped in a mobile communication terminal (such as a portable electronic device). For example, functions, such as an entertainment function (such as a game function), a multimedia function (such as a music/video reproducing function), a communication and security function for mobile banking, a schedule management function, and an e-wallet function, are integrated in the portable electronic device.
The portable electronic devices supporting various functions or applications (such as an electronic scheduler, a portable multimedia reproducer, a mobile communication terminal, and a tablet PC) have been generally equipped with a display device and a battery in a bar-type, a folder-type, or a sliding-type exterior appearance. Recently, the portable electronic devices have been miniaturized to be wearable on a portion of a body (such as a wrist or a head) and become commercially available.